West African leaders are threatening to use force against incumbent Ivorian Coast President Laurent Gbagbo unless he accepts election results and gives up power.
Heads of state said after meeting in Nigeria Friday that they will send a delegation to Mr. Gbagbo in hopes of convincing him to step down peacefully.
They said if he refuses, neighboring countries will have "no alternative" but to take other measures, including the use of "legitimate force," to enforce the election results.
The African Union, United Nations, and many countries have recognized Alassane Ouattara as the winner of the November election. However, Mr. Gbagbo has rejected all attempts to make him leave office.
The United Nations says more than 170 people have been killed in post-election violence. It also says Mr. Gbagbo's forces and masked gunmen are blocking access to the site of a possible mass grave, in the village of N'Dotre.
Friday's statement by the West African bloc ECOWAS intensified the international pressure on Mr. Gbagbo to leave office.
On Thursday, west Africa's central bank cut off his access to state money, and said money would only be given to what it called Mr. Ouattara's legitimate government. Also Thursday, the U.N. General Assembly decided it will recognize Mr. Ouattara's diplomats instead of Mr. Gbagbo's.
Mr. Gbagbo has demanded that U.N. peacekeepers in Ivory Coast depart. But the U.N. has said the troops will stay, and the U.S. has said it is seeking ways to increase the size of the force.
Mr. Gbagbo is facing internal pressure as well. In a speech, Mr. Ouattara called on the Ivorian army to desert the incumbent leader. State television, which was under Mr. Gbagbo's control, went off the air Thursday with no explanation.
The presidential election was meant to stabilize Ivory Coast, eight years after a civil war split the country into rebel- and government-controlled areas.